Automatic dialer with a programmable pause

ABSTRACT

An automatic telephone dialer for serially placing outgoing telephone calls from a facsimile terminal or the like in response to successive sets of dialing instructions read by a raster input scanner may be programmed to automatically pause between successive calls to give incoming calls access to the terminal.

BACKGROUND OF THE INVENTION

This invention relates to methods and means for utilizing raster inputscanners as readers for automatic telephone dialing equipment and, moreparticularly, to automatic telephone dialing methods and means forfacsimile systems and the like.

Facsimile systems have gained widespread commercial acceptance becausethey offer rapid and accurate, long distance communication of most anytype of graphic information (e.g., handwritten and printed pages,charts, graphs, and drawings), subject to minor exceptions which areprincipally attributable to resolution limitations. As is known, a basicfacsimile system comprises a transmitting terminal and a receivingterminal which are interconnected by a communications link. Customarily,there is a raster input scanner within the transmitting terminal forserially converting or remapping the two dimensional information contentof an original document (generally called a "subject copy") into acorresponding, one dimensional video signal. Moreover, the transmittingterminal normally includes a modulator for modulating a suitable carriersignal in accordance with the video signal so that a passband signal isprovided for transmission to the receiving terminal via thecommunications link. Accordingly, the receiving terminal typically has ademodulator for recovering the video signal and a raster output scannerfor serially printing a more or less exact replica or "facsimile" of thesubject copy in response to the video signal.

Dedicated transmitters and receivers are sometimes used as terminals forfacsimile systems, but the more common practice is to employtransceivers which are selectively operable in a transmit mode or areceive mode. As a general rule, the communications link or channel forfacsimile communications is furnished on demand by a telephone dialsystem, such as the public switched telephone network.

Substantial effort and expense have been devoted to automating facsimilesystems, thereby reducing the amount of operator intervention andsupervision required. For example, the Xerox 200 Telecopier transceiver,which is manufactured and sold by Xerox Corporation, operatesessentially automatically, with the noteable exception of being able toplace outgoing calls. Specifically, that unit automatically answersincoming calls and automatically disconnects incoming and outgoingcalls. It can be automatically set in response to remotely generatedcommands to operate in a transmit mode or a receive mode at any one ofits available document transmission rates of 2, 3, 4 and 6 minutes/page.Furthermore, the 200 transceiver includes an automatic document feederwhich permits it to sequentially scan a plurality of subject copiesautomatically when operating in a transmit mode. Additionally, there isa roll fed paper supply which permits that unit to automatically printsuccessive facsimile copies when operating in a receive mode. For a moredetailed description of that transceiver, reference may be made to Masonet al. U.S. Pat. No. 3,869,569, which issued Mar. 4, 1975 on a"Facsimile Transceiving Apparatus," and to Perreault et al. U.S. Pat.No. 3,889,057, which issued June 10, 1975 on a "Facsimile CommunicationSystem." Hence, those patents are hereby incorporated by reference.

General purpose automatic telephone dialers have been available forseveral years. Nevertheless, few, if any, facsimile terminals have beenequipped with automatic telephone dialing equipment prior to thisinvention.

SUMMARY OF THE INVENTION

Against the foregoing background, a general aim of the present inventionis to provide methods and means for utilizing raster input scanners asreaders for automatic telephone dialers. A more detailed, related objectis to provide methods and means for translating raster scanned addressindicia into the dial pulses or frequencies necessary to place outgoingtelephone calls.

More particularly, an object of this invention is to provide economicalmethods and means for automatically placing outgoing telephone callsfrom unattended facsimile terminals. In more detail, an object is toprovide methods and means for utilizing the raster input scanners ofconventional facsimile transmitters and transceivers as readers forautomatic telephone dialing equipment.

Even more pointedly, an object of the present invention is to providemethods and means for automatically placing outgoing telephone callsfrom unattended facsimile terminals at any preselected time of day,whereby those terminals can carry out facsimile comunications at themost convenient time of day, such as during non-business hours whentelephone traffic and charges are usually relatively low.

Another specific object of the present invention is to provide methodsand means for automatically placing outgoing calls from unattendedmulti-speed facsimile terminals and for setting-up such terminals tooperate in an individually preselected mode and at an individuallypreselected document transmission rate during each of those calls.

Still another object of this invention is to provide facsimile terminalswith automatic dialing and control equipment of the foregoing type,without impairing the existing ability of those terminals to functionunder manual or remote control.

Briefly, to carry out these and other objects of the invention, afacsimile terminal is equipped with an automatic dialer whichtemporarily seizes control of the terminal when a unique recognitionpattern at the leading edge of an address card is scanned. Each addresscard has a specially formatted instruction field which is divided intorows and columns to allow for the entry of mark sense indiciarepresenting dialing and terminal control instructions. When a completeand unambiguous set of instructions are scanned, the dialerautomatically makes a telephone call in accordance with the dialing andterminal control instructions. If the call cannot be completed or if theinstructions are incomplete or unambiguous, the job is aborted and theterminal is returned to a standby state. If, on the other hand, the callis completed, communications are carried out in the usual way.

Preferably, the facsimile terminal has an automatic document feeder sothat one or more address cards and, if appropriate, one or more sets ofsubject copies may be preloaded into the feeder to be scanned oncommand. That command may be entered as a simple start instruction or asa delayed start instruction. If a delayed start is used, scanning isinitiated by the automatic dialer when the actual time of day comes intocoincidence with a preselected time of day for the delayed start.

BRIEF DESCRIPTION OF THE DRAWINGS

Still further objects and advantages of the present invention willbecome apparent when the following detailed description is read inconjunction with the attached drawings, in which:

FIG. 1 is a simplified elevational view of a facsimile transceiver whichis equipped with an automatic telephone dialer constructed in accordancewith the present invention;

FIG. 2 is a fragmentary elevational view, partially in section, of anautomatic document feeder for the transceiver of FIG. 1;

FIG. 3 is another partially sectioned and fragmentary elevational viewillustrating the optics included within the exemplary transceiver shownin FIG. 1;

FIG. 4A and 4B diagrammatically illustrate a typical sequence of addresscards, pause cards and subject copies as stacked in the input tray ofthe automatic document feeder shown in FIG. 2;

FIG. 5A is an enlarged front view of an address card;

FIG. 5B is an enlarged, fragmentary view of a pause card;

FIG. 6 is an enlarged top plan view of the automatic telephone dialershown in FIG. 1;

FIG. 7 is a functional block diagram of the automatic dialer incombination with the exemplary transceiver;

FIG. 8 is a diagram indicating the manner in which FIGS. 9-16 areintended to be assembled;

FIGS. 9-16, when assembled as indicated in FIG. 8, combine to form amore detailed block diagram of the automatic dialer in combination withthe exemplary transceiver; and

FIGS. 17 and 18, when joined as indicated at AD, RTN and AS, combine toform a functional flow chart illustrating the basic operation of theautomatic telephone dialer.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

While the invention is described in some detail hereinbelow withspecific reference to a single illustrated embodiment, it is to beunderstood that there is no intent to limit it to that embodiment. Onthe contrary, the aim is to cover all modifications, alternatives, andequivalents falling within the spirit and scope of the invention asdefined by the appended claims.

A. A Synergistic Environment

Turning now to the drawings, and at this point especially to FIG. 1,there is an automatic telephone dialer 31 which is particularly wellsuited for use with a dedicated or non-dedicated facsimile terminal 32having a raster input scanner 33 (FIG. 3). Indeed, there is synergism inthat combination. Specifically, in keeping with one of the moreimportant aspects of this invention, the automatic dialer 31 placesoutgoing telephone calls from the terminal 32 and conditions theterminal 32 for participation in facsimile communications in response todialing and terminal control instructions which are read into the dialer31 by the input scanner 33 of the terminal 32. It has, in short, beenrecognized that the raster input scanner 33 of a more or lessconventional facsimile transmitter or transceiver terminal 32 canadvantageously be utilized as an instruction reader for the dialer 31,thereby avoiding the extra expense and complexity of having to furnishthe dialer 31 with a separate reader.

As shown, the automatic dialer 31 comprises a hook switch 34 forsupporting a telephone handset 35 and a keyboard 36 for manuallyentering dialing and dialer control instructions. Dialing instructionsentered via the keyboard 36 are accepted and executed by the dialer 31only if the handset 35 is "off-hook", which indicates that the dialer 31is being operated in a manual mode. All other instructions entered viathe raster input scanner 33 and the keyboard 36 are accepted andexecuted while the handset 35 is "on-hook", thereby allowing the dialer31 to perform in an automatic mode. For feeding raster scannedinstructions and terminal status signals from the terminal 32 to thedialer 31 and for feeding terminal control signals and dialing pulses orfrequencies from the dialer 31 to the terminal 32, there suitably is amulti-lead cable 37 coupled between the dialer 31 and the terminal 32.

In practice, the construction and operation of the automatic dialer 31is unavoidably dependent on the functional characteristics andcompatability requirements of the facsimile terminal 32. Therefore, anexemplary terminal 32 will be briefly reviewed to set the stage for amore detailed treatment of the dialer 31.

To simplify this disclosure, the illustrated facsimile terminal 32comprises a Xerox 200 Telecopier transceiver 38 which is interfacedwith, say, the public switched telephone network by a standard dataaccess arrangement 39 (FIG. 7), such as CBS 1001F data coupler. Ageneral familiarity with the functional characteristics and thecompatability requirements of that commercially available equipment isassumed. Consequently, the following discussion focuses on the featureswhich are most relevant to the automatic dialer 31.

Preferably, the automatic dialer 31 supplements the facsimile terminal32, whereby the existing capabilities of the terminal 32 are preserved.For example, the 200 Telecopier unit 38 is a half duplex facsimiletransceiver which is selectively operable under local or remote controlto function in a transmit mode or a receive mode at a documenttransmission rate of two, three, four or six minutes per standard 81/2 ×11 inch page. Moreover, the combination of that transceiver 38 with asuitable data access arrangement or DAA 39 provides the terminal withthe ability to automatically answer incoming telephone calls and toautomatically disconnect and outgoing calls.

1. An Automatic Document Feeder

Referring to FIG. 2, the transceiver 38 has an automatic document feeder41 (shown only in part) for serial feeding successive documents from aninput tray 42 to an output tray 43 (FIG. 1) via a scan platen 44. Asexplained in additional detail in the aforementioned Mason et al. U.S.Pat. No. 3,869,569, the illustrated document feeder 41 has a bottomfeeding, retard-type sheet separator 45 for separating the documentsupstream of the scan platen 44. For that reason, the documents to bescanned are loaded into the input tray 42 image side down and arestacked in consecutive order so that the first document is at the bottomof the stack and the last is at the top.

Concentrating for a moment on the sheet separator 45, there is a retardwheel 51 which is frictionally engaged with an endless traction belt 52,thereby forming a feed nip 53 inboard of and slightly above the leadedge of the platen 44. The input tray 42 is inclined downwardly towardthe nip 53. Additionally, when a feed command is given, the tractionbelt 52 positively urges the bottommost document in the input tray 42into the feed nip 53. To that end, the traction belt 52 is extendedthrough a slot (not shown) in the lead edge of the scan platen 44 and istrained around a drive wheel 54, an adjustable idler-type tension pulley55, and an eccentric idler wheel 56. The eccentric 56 is radiallyaligned with a slot (also not shown) in the bottom of the input tray 42.Furthermore, the maximum and minimum radii of the eccentric 56, assupplemented by the finite thickness of the belt 52, are selected to begreater than and less than, respectively, the distance between thebottom of the input tray 42 and a generally parallel axis of rotationfor the eccentric 56.

When a feed command is given, the drive wheel 54 is rotatably driven (bymeans not shown) in the direction of the arrow. Sufficient tension ismaintained on the traction belt 52 to cause it to revolve in response tothe rotation of the drive wheel 54, and that rotation is translatedthrough the belt 52 to the tension pulley 55 and the eccentric 56. As aresult of the rotation of the eccentric 56, the traction belt 52 isperiodically lifted through the slot in the bottom of the input tray 42and brought into frictional engagement with the lower surface or imageside of the bottommost document in the input tray 42. Therefore, thatdocument is positively urged into the feed nip 53 as the traction belt52 continues to revolve. Any other documents in the input tray 42 areinhibited from entering the feed nip 53 because there is sufficient dragon the retard wheel 51 to prevent it from freely rotating. However, therotation of the eccentric 56 periodically and alternately creates andreleases a tension differential between the upper and lower reaches ofthe traction belt 52. When that differential is released or equalized,an impulse-like force of sufficient magnitude to index the retard wheel51 is generated. Hence, the wear surface of the retard wheel 51 (i.e.,the surface in frictional, sliding contact with the traction belt 52) isperiodically advanced circumferentially thereby causing the retard wheel51 to wear more or less uniformly.

In keeping with still further teachings of the above-identified Mason etal. patent, the document feeder 41 suitably includes a series of feedrollers (not shown) downstream of the sheet separator 45 for feeding thesuccessive documents across the scan platen 44. Those rollers and thedrive wheel 54 of the sheet separator 45 are typically driven in timedsynchronism with the scanning cycle (described hereinbelow) of thetransceiver 38 so that the documents enroute across the platen 44 areincrementally advanced a predetermined scan pitch distance during theflyback portion of each scanning cycle. If different scan pitches are tobe accommodated, a factor common to all of the possible pitches is usedas a basic step length, and the number of steps allotted to eachscannning cycle is then controlled as a function of the selected scanpitch.

2. A Scanner/Printer Mechanism

Turning to FIG. 3, the transceiver 38 has a laser 61 and a scan mirror62 which are alternatively and selectively utilized by the raster inputscanner 33 and by a raster output scanner 63. This portion of thetransceiver 38 is described in some detail in Mason U.S. Pat. No.3,870,816, which issued Mar. 11, 1975 on an "Optical System forTransmit/Receive Mode Conditioning of Facsimile Transceivers" and whichis hereby incorporated by reference. Additionally, the aforementionedPerreault et al. and Mason et al. patents elaborate on the relationshipof the input and output scanners 33 and 63 to the transceiver 38.

Reviewing the optics of the transceiver 38 on a functional level, itwill be seen that the collimated light beam emitted by the laser 61 isreflected from a first corner mirror 64 to a second corner mirror 65 andthen to the scan mirror 62. A galvanometer-type drive mechanism 66cyclically rotates the scan mirror 62 back and forth through apredetermined planar scan angle, thereby periodically deflecting orsweeping the laser beam in a predetermined line scanning direction.Downstream of the scan mirror 62 there is a flip mirror 67 which isselectively inserted into and removed from the optical path for thedeflected laser beam so that the beam is alternatively routed to theraster input scanner 33 or the raster output scanner 63.

Unidirectional input scanning and output printing are achieved bysynchronously blanking the laser 61 while the scan mirror 62 iscounterrotating or flying back from an end of scan to a start of scanposition. Preferably, the counterrotation of the scan mirror 62 iscarried out at an appreciably higher angular velocity than the forwardrotation so that only a relatively brief portion of each scanning cycleis consumed by the fly back period.

More particularly, when the transceiver 38 is operating in a transmitmode or a test mode, the flip mirror 67 is maintained in its solid lineposition (as shown in FIG. 3) to intercept and reflect the deflectedlaser beam from the scan mirror 62 to an elongated mirror 71 within theinput scanner 33. During the forward rotation of the scan mirror 62, thelaser 61 is excited to provide an output beam of constant intensity, andthat beam is reflected from the mirror 71 to sweep across a line-likescanning station 72 on the scan platen 44. Hence, the documents to bescanned are illuminated in accordance with a predetermined rasterscanning pattern as they pass over the scanning station 72 in adirection generally perpendicular to the line scanning direction. Toconvert the two dimensional information content of the documents into acorresponding one dimensional video signal, there is a scan line lengthphotodetector (not shown) for generating a video signal in response tothe light which is diffusely reflected from the successively illuminatedareas of the documents.

In contrast, when the transceiver 38 is operating in a receive mode, thelaser 61 is modulated in accordance with an incoming video signal, andthe flip mirror 67 is maintained in its phantom line position so thatthe deflected laser beam passes from the scan mirror 62 to anotherelongated mirror 73 in the raster output scanner 63. The laser beamreflected from the mirror 73 sweeps across a line-like printing station74. Furthermore, the photoreceptor 75 of a xerographic processor 76(shown only in part) is incrementally advanced past the printing station74 during the fly back portion of each scanning cycle, at a ratedependent on the document transmission time selected, and in a directiongenerally perpendicular to the line scanning direction. Consequently,the video modulated laser beam provided by the laser 61 exposes thephotoreceptor 75 in accordance with a predetermined raster scanningpattern to create a latent electrostatic image of the facsimile copy. Ofcourse, that copy is then usually printed through the use of standardxerographic printing techniques.

B. The Automatic Dialer

Looking now to FIGS. 1-5, in keeping with this invention, the automaticdialer 31 is capable of executing dialing and terminal controlinstructions which are received from the raster input scanner 33 whenaddress cards 81a - 81c bearing mark sense indicia representing thoseinstructions are scanned. In practice, the address cards 81a - 81c andany associated subject copies 82 and 83 advantageously are loaded intothe input tray 42 of the automatic document feeder 41 so that thescanning can be initiated on command.

1. An Address Card Format

Focusing on FIGS. 3-5, the raster input scanner 33 makes no distinctionbetween address cards 81a - 81c and ordinary subject copies 82 and 83.However, a distinctive bar code 84 is printed along the leading andtrailing edge borders on the front and back of each of the address cards81a - 81c (the bar codes 84 on the loading edge borders of the back andfront of the address card 81b can be seen in FIGS. 4 and 5,respectively). Consequently, whenever the input scanner 33 starts toscan one of the address cards 81a - 81c, a predetermined unique sequenceof black and white ("1" and "0") picture elements is generated to signalthe automatic dialer 31 that an address card is being scanned, even ifthe card happens to be inverted or upside down.

To accommodate mark sense indicia representing operator selectedterminal control and dialing instructions, there is an instruction field85 comprising a plurality of orthogonal columns and rows on the front ofeach of the address cards 81a - 81c. As best shown in FIG. 5, thecolumns extend in the scan pitch direction and are equidistantly spacedin the scanning direction to distinguish between mutually exclusiveinstructions. The rows, on the other hand, extend in the scanningdirection and are equidistantly spaced in the scan pitch direction todistinguish between successive, consistent instructions. Here, forexample, the first or uppermost row is several columns wide to provide aselection of mutually exclusive terminal control instructions callingfor the transceiver 38 to operate in a transmit (send) mode at adocument transmission rate of two, three, four, or six minutes per pageor in a receive (polling) mode at a remotely determined documenttransmission rate. Next, there is a single column wide row which isdedicated to a dial tone instruction so that the automatic dialer 31initiates the dialing only after pausing for a predetermined time periodor confirming that dial tone is being received, depending on whetherblind dialing is selected or not as described hereinbelow. The followingrows are each several columns wide to allow for identification of thedigits (0-9) which are to be serially dialed and of the intermediatedial tones (--) which should be received while placing an outgoingtelephone call to a predetermined, remote station.

As illustrated, the address cards 81a - 81c are asymmetrical. They areproperly oriented for reading only if they are presented to the inputscanner 33 front or instruction field side down and leading edgeforward. Hence, if a misoriented address card is encountered by theinput scanner 33, the automatic dialer 31 initiates a job abort process.That process is triggered whenever the automatic dialer 31 fails toreceive instructions from the input scanner 33 within a predeterminedperiod of time after detecting that an address card is being scanned.

A lapsed time decoding process is used by the automatic dialer 31 toidentify or decode the instructions represented by the mark senseindicia entered within the instruction fields 85 of the address cards81a - 81c. To that end, each row of the instruction field 85 is precededat a preselected distance by another distinctive bar code 86 so that theinput scanner 33 supplies the automatic dialer 31 with anotherpredetermined, unique sequence of black and white picture elements uponreaching a predetermined point in the scanning of each of those rows,thereby establishing a row-by-row timing reference for the automaticdialer 31. The order, spacing, and meaning of the potential instructionsassociated with the different rows of the instruction field 85 areknown, and the sweep velocity of the input scanner 33 is also known.Therefore, the automatic dialer 31 decodes or identifies the selectedinstructions on the basis of the amount of time which passes during thescanning of each row of the instruction field 85 between the moment thatthe timing reference for that row is established and the moment thatpicture elements are received to indicate that a mark representing aselected instruction is being scanned.

Instructions represented by appropriate mark sense indicia enteredwithin successive rows of the instruction field 85 of an address cardare accepted and executed by the automatic dialer 31, provided that oneand only one instruction is marked for selection per row. If more thanone instruction is so marked within any given row, all instructions fromthat row are rejected because there is an inherent ambiguity. If, on theother hand, there are one or more intermediate rows of the instructionfield 85 which have no instructions marked for selection, the automaticdialer 31 accepts, but does not execute, instructions represented byappropriate mark sense indicia entered in the subsequent rows becausethere is a potential ambiguity -- viz., were the intermediate rowssimply skipped or were instructions inadvertently omitted?

Some skew of the address cards 81a - 81c relative to the scanningstation 72 of the input scanner 33 is normal and expected, especiallywhen the automatic document feeder 41 or similar device is used. Thus,to ensure that the address cards 81a - 81c can be accurately readdespite that skew, the printed bar codes 84 and 86 and the instructionrepresenting mark sense indicia are preferably several times longer, asmeasured in the scan pitch direction, than the coarsest scan pitch ofthe input scanner 33.

2. A Keyboard/Display Unit for the Automatic Dialer

As shown in FIGS. 1 and 6, the keyboard 36 and a display 92 are employedfor purposes of operator interaction with the automatic dialer.Typically, the keyboard 36 comprises appropriately referencedalphanumeric keys and control keys for the operator to use in enteringdialing and dialer control instructions into the automatic dialer 31.The display 92, on the other hand, has numerical indicia and suitableword legends which are selectively illuminated to keep the operatorabreast of the status and performance of the automatic dialer 31.

Provision is made for selectively operating the automatic dialer 31 inan automatic mode or a manual mode to execute dialing instructionsentered via the input scanner 33 or the keyboard 36, respectively. Whenan outgoing call is to be placed without scanning an address card, theoperator manually prepares the transceiver 38 to participate infacsimile communications with a remote terminal and then removes thehandset 35 from the hook switch 34 to signal the automatic dialer 31that the manual mode has been selected. After confirming that initialdial tone is being received at the handset 35, the operator seriallydepresses appropriate ones of the alphanumeric keys on the keyboard 36while continuing to listen for and, if necessary, pausing to receive anyintermediate dial tones associated with the telephone number of theremote terminal, much in the same manner as is done when placing anordinary telephone call. The automatic dialer 31 executes the keyboardentering dialing instructions in real time. Finally, when the call isanswered, the operator listens for a ready tone from the remote terminaland then replaces the handset 35 on the hook switch 34 to initiate thefacsimile communications. If an error is made in entering the dialinginstructions or if the remote terminal fails to answer the telephonecall or fails to provide a ready tone, a clear key is depressed to clearthe dialing instructions which have been entered, thereby preparing thedialer 31 for another try at placing that same call or a different call.

All other dialing, terminal and dialer control instructions are enteredinto and executed by the automatic dialer 31 while the handset 35 is inplace on the hook switch 34 to signal that an automatic mode ofoperation is called for. An immediate or manual start instruction isentered if the operator depresses a start key. Alternatively, theoperator may choose to enter a delayed start instruction. In that event,the operator depresses the time set key and then enters a selected timeof day for the delayed start by sequentially depressing appropriate onesof the alphanumeric keys followed by either the AM or PM key.Additionally, the operator may cause the contents of a recall memory,which is described hereinbelow, to be read out byte-by-byte on thedisplay 92 by repeatedly depressing a recall key at a rate in excess ofa predetermined memory recycling rate. Moreover, if the recall key andan erase key are repeatedly and alternately depressed at a ratesufficient to prevent recycling, the recall memory is cleared during theread out process. Also, there is a test key which the operator mayoperate to obtain a read out on the display 92 of the dialing andterminal control instructions read off an address card by the inputscanner 33, without having those instructions executed by the automaticdialer 31.

Shared function keys may be utilized on the keyboard 91, provided thatprovision is made for discriminating between the different instructionswhich may be furnished by depressing such a key. For example, in theillustrated embodiment, the alphanumeric "0" instruction and the dialercontrol "erase" instruction are suitably associated with a single keybecause the automatic dialer 31 requires that the "erase" instruction beimmediately preceded by a "recall" instruction, thereby providing abasis for discriminating between the two different instructionsassociated with that one key.

The display 92 suitably comprises a gas discharge display panel havingseveral spaced apart numerical display elements and legend displayelements. In keeping with accepted practices, each of the numericaldisplay elements has a solid anode and a segmented cathode -- viz., thecathode is composed of seven electrically isolated segments which arearranged so that any numeral (0-9) or a dash (--) may be displayed byselectively energizing appropriate ones of those x cathode segments. Theanodes of the several numerical display elements are electricallyisolated from one another, but the positionally corresponding cathodesegments are electrically interconnected. Similarly, each of thenumerical display elements includes an electrically isolated anode and asegmented cathode. However, each of those segments is sculptured todefine an individual letter or symbol of a word legend such as "send","receive", "test", "recall" or "pause" or of a symbolic legend, such as"AM", "PM" or ":". External electrical connections are made between thecathode segments of each individual legend display element, and internalelectrical connections are made between the cathode segments ofdifferent legend display elements.

Under quiescent conditions, the display 92 provides a runningtime-of-day indication. If a delayed start instruction is entered intothe automatic dialer 31, the display 92 additionally displays thetime-of-day which has been selected for the delayed start. Hence, theoperator can determine at a glance whether there is a delayed start tobe executed, and, if so, the amount of time remaining until the delayedstart is to be carried out. A recall indication is displayed, withoutblanking the actual or delayed start time-of-day indication, if thesubsequently described recall memory contains instructions which havenot been executed for one reason or another. Indeed, if the recallmemory is nearly or completely full, a flashing recall indication isdisplayed to warn the operator that the automatic dialer 31 is in a softstop state.

To limit the number of display elements required of the display 92, theactual and delayed start time-of-day indications are blanked wheneverthe automatic dialer 31 receives an instruction to execute a manual or adelayed start instruction, a test instruction or a recall instructionand whenever the automatic dialer 31 is switched into a manual mode ofoperation. When a manual start, a delayed start or a test instruction isbeing executed, the display 92 displays the dialing and terminal controlinstructions which are being read into the automatic dialer 31 by theinput scanner 33. Similarly, when a recall instruction is beingexecuted, the display 92 displays the data read out of the recallmemory. Lastly, when the automatic dialer 31 is being operated in amanual mode, the display 92 displays the dialing instructions enteredvia the keyboard 91.

3. A Program Controlled Embodiment

Referring to FIG. 7, a practical and economical embodiment of theautomatic dialer 31 takes advantage of the simplicity and flexibilityassociated with the use of a programmed system controller 101. Forexample, relatively straightforward manually set controls 102 may beincluded to allow the operator to select (a) pulse or (b) dual tone,multiple frequency (DTMF)(c) blind or (d) dial tone responsive dialing.An automatic retry capability may be included in the system controller101 so that calls that are not completed are automatically retried for apredetermined number of times, and the operator may use another of themanually set controls 102 to cause the retrys to be performed after along or short pause. Additionally, the automatic dialer 31 can readilyrespond to the indication provided by the hook switch 34 (FIG. 1) toaccommodate a manual or an automatic mode of operation. In short, theseand other features of this invention are more readily implemented insoftware than in hardware.

The system architecture depicted in FIG. 7 will be better understoodupon referring to the specific embodiment of the automatic dialer 31which is illustrated by FIGS. 9-16 when assembled as shown in FIG. 8.

Turning to FIGS. 9-16, it will be seen that the system controller 101 isPPS-4 microcomputer which is manufactured and sold by RockwellInternational Corporation, Microelectric Device Division. That unit isdescribed in detail in "PPS-4 Microcomputer Programming Manual,"Rockwell International Corporation Microelectronic Device Division,Document No. 29400 N31, Oct. 1974. That manual is hereby incorporated byreference, but a brief review of the PPS-4 microcomputer might still behelpful.

In keeping with a standard configuration for the PPS-4 microcomputer,the system controller 101 is a four bit parallel processor having acentral processing unit (CPU) 102 comprising a twelve bit address bus103, an eight bit instruction/data bus 104 and a single bit multiplexedcontrol bus 105. A read only program memory (ROM) 106 and a randomaccess data memory (RAM) 107 selectively interact with theinstruction/data bus 104 in response to address words which are appliedto the address bus 103 by a program address register 108 and a dataaddress register 109, respectively. Specifically, when the ROM 106 isaddressed by the program address register 108, program instructions arefetched from a predetermined location in the ROM 106 and fed through theinstruction/data bus 104 for application to an instruction decoderegister 111, a plurality of general purpose input/output (I/O) devices112--114, and a keyboard/display (K/D) interface 115. Conversely, whenthe ROM 107 is addressed by the data address register 109, data iscommunicated between the RAM 107 and a four bit accumulator 116 via theinstruction/data bus 104. If a write or load instruction is beingexecuted, bits 5-8 of the instruction/data bus 104 are used to transferthe contents of the accumulator 116 into the addressed location of theRAM 107. If, on the other hand, a read or fetch instruction is beingexecuted, bits 1-4 of the instruction/data bus 104 are used to transferdata from the addressed location of the RAM 107 into the accumulator116.

A clock 117 generates A clock pulses at a base frequency of, say 199KHz., and B clock pulse at twice that frequency or 398 KHz. Those clockpulses are applied to the RAM 107, the input/output devices 112-114, andthe keyboard/display interface 115, thereby establishing a four phasetiming cycle for the controller 101. The buses 103-105 are cleared orreset to a low ("0") logic level and the CPU 102 is prepared to executeany pending instructions during the first and third phases of eachcycle. During the second phase of each timing cycle, the address inputsof the RAM 107 are inhibited so that the address bus 103 is availablefor feeding an address word from the program address register 108 to theROM 106, thereby identifying the next instruction which is to be given.

If the preceding instruction from the ROM 106 was a data write or readinstruction, the instruction/data bus 104 is employed during the secondphase of the timing cycle for transferring the data between the RAM 107and the accumulator 116. At the same time, the instruction decoder 111sets a W I/O control bit on the control bus 105 to a high ("1") or a low("0") logic level to signal the RAM 107 whether a data write or readinstruction is to be performed. When a data read instruction is pending,the location of the data which is to be performed. When a data readinstruction is pending, the location of the data is to be transferredfrom the RAM 107 to the accumulator 116 is pre-identified by virtue ofan address word which was applied to the RAM 107 by the data addressregister 109 during the fourth phase of the preceding cycle. Therefore,that instruction is executed during the second phase of the existingcycle. However, a data write instruction is not executed until thefourth phase of the existing timing cycle is reached. At that time, thedata address register 109 feeds an address word through the address bus103 to the RAM 107, thereby identifying a desired storage location forthe data transferred from the accumulator 16 to the RAM 107.

The next instruction is read out of the ROM 106 through theinstruction/data bus 104 during the fourth phase of each timing cycle.That instruction is immediately examined by the instruction decoderegister 111, whereby the W I/O control bit on the control bus 105 isset to a high ("1") or a low ("0") logic level during the fourth phaseof the timing cycle depending on whether the new instruction is aninput/output instruction or a data memory (i.e., read or write)instruction. If another data memory instruction is being given, theabove-described process is repeated. If, on the other hand, aninput/output instruction is being given, the process is modified toprovide for a direct transfer of data between the accumulator 116 and anappropriate one of the input/output devices 112-114 of thekeyboard/display interface.

Input/output instructions are each composed of two bytes. The first byteis fed from the ROM 106 to the instruction decode register 111 duringthe fourth phase of one timing cycle, whereby the W I/O control bit onthe control bus 105 is then set to a high ("1") logic level. Thatenables the input/output devices 112-114 and the keyboard/displayinterface 115 and also inhibits the RAM 107 from feeding data onto oraccepting data from the instruction/data bus 104 during the next timingcycle. When the second phase of that next cycle is reached, the programaddress register 108 feeds the address word identifying the location ofthe second byte of the input/output instruction to the ROM 106 over theaddress bus 103. That byte is, in turn, read out of the ROM 106 duringthe fourth phase of that same cycle and is then applied to theinput/output devices 112-114 and the keyboard/display interface 115 viathe instruction/data bus 104. Bits 5-8 of the second byte of theinput/output instruction point to a specific one of the devices 112-115,while bits 1-4 identify the operation which is to be performed by thatdevice.

The program address register 108 is a twelve bit register which isorganized into two sections. The six most significant bits within theregister 108 provide a fixed count which can be changed only underprogram control, while the six least significant bits define a runningcount which is automatically incremented by one for each timing cycle ofthe controller 101, unless otherwise directed under program control. Toaccommodate branch routines and subroutines, a twelve bit program returnregister 121 and a twelve bit save register 122 are connected in serieswith the program address register 108 to provide a two level stack forholding program reentry addresses. For obtaining additional stacking ofreentry addresses in the RAM 107, the program return register 121 issplit into three segments of four bits each which can be sequentiallyshifted into and out of the accumulator 116 under program control.Moreover, the bits being transferred from the program return register121 to the accumulator 116 may be operated on by an arithmetic logicunit (ALU) 123 if an appropriate program instruction is given.

Similarly, the data address register 109 is a twelve bit register whichis divided into three separate four bit segments. Usually, the countstored within the register 109 is incremented or decremented by oneunder program control for each timing cycle of the controller 101.However, the four most and least significant bits of that count may bedirectly modified under program control by the accumulator 116, and theother or middle four bits may be indirectly modified under programcontrol by the accumulator 116 through an exchange register 124. Theexchange register 124 is a temporary four bit static storage registerwhich may be used to temporarily store the contents of the accumulator116 or to transfer the contents of the accumulator 116 into the middlefour bit positions of the data address register 109.

As will be appreciated, the accumulator 116 is the primary storage forthe CPU 102. It participates in the exchange and transfer of all activeinput and output data, whether received from or enroute to the RAM 107,the data address register 109, any one of the input/output devices112-114, the keyboard/display interface 115, the program return register121, the arithmetic logic unit 123, or the exchange register 124. Datamay be read into or out of the accumulator 116, under program control,via bits 1-4 and 5-8, respectively, of the instruction/data bus 104during the second phase of any timing cycle of the controller 101.Furthermore, data may be transferred to or from the accumulator 16internally of the CPU 102 during other phases of the timing cycle sincethose transfers are carried out without using the instruction/data bus104. For example, if an instruction commanding a modification of thecontents of the program address register 108 is given, the flow of datafrom the accumulator 116 to the program return register 121 and fromthere to the program address register 108 is completely isolated fromthe instruction/data bus 104.

The accumulator 116, the arithmetic logic unit 123, and a one bit carryregister 125 provide a four bit parallel adder having carry-in andcarry-out capabilities, whereby data words which are multiples of fourbits may be accommodated.

Additionally, there are a pair of flip-flops 126 and 127 which may beindependently set, reset and tested under program control in response tosignals supplied by the instruction decode register 111. That means thatthe flip-flops 126 and 127 may function as status indicators. Here, forexample, the flip-flops 126 and 127 are set as a section of the RAM 107which is dedicated to a recall memory approaches and reacts,respectively, a fully loaded state, whereby the recall indication on thedisplay 92 is flashed as the last few recall memory storage locationsare being filled and then the automatic dialer 31 is brought to a softstop if the last of those locations is filled.

The input/output devices 112-114 for this embodiment are the standardgeneral-purpose input/output devices available from RockwellInternational Microelectronic Device Division (under Part No. 10696) foruse with the PPS-4 microcomputer. Such of them includes static twelvebit input sampling gates, together with a twelve bit output buffer whichcan be modified under program control.

As illustrated, to carry out the present invention, provision is made inthe automatic dialer to provide the following input control signals fora Xerox Telecopier transceiver under program control:

    ______________________________________                                                Significance of True or High ("1")                                    Signal  Logic Level State                                                     ______________________________________                                        SCANS   A forced indication that the trail edge switch                                (not shown) in ADF 41 is actuated.                                    TRAYS   A forced indication that at least one document                                remains in tray 43 of ADF 41.                                         ENADF   A document is to be fed by the ADF 41.                                FSTSPN  The ADF 41 is to feed the document at a fast                                  feed rate.                                                            SENDL   A "send" lamp (not shown) on the scanner/printer 33                           is to be lit.                                                         ONLINL  An "on-line" lamp (not shown) on the scanner/                                 printer - 33 is to be lit.                                            TESTML  A "test" lamp (not shown) on the scanner/printer 33                           is to be lit.                                                         RECVL   A "receive" lamp (not shown) on the scanner/                                  printer 33 is to be lit.                                              ASPSWN  Document transmission rate for scanner/printer 33                             to be selected independently of automatic dialer 31.                  TESTBN  Test mode command not given to scanner/printer 33.                    EOTAL   Sound an audible end-of-transmission alarm (not                               shown) within the scanner/printer 33.                                 DMTRN   Enable main drive motor (not shown) of scanner/                               printer 33.                                                           ADSP2N  Automatic dialer 31 not to establish a two, three,                    ADSP3N  four or six minute, respectively, document trans-                     ADSP4N  mission rate for the scaner/printer 33.                               ADSP6N                                                                        ADBMDN  Enable billing meter (not shown) within the                                   scanner/printer 33.                                                   DDISSN  Scanner/printer 33 enabled to detect a disconnect                             by the DAA.                                                           DISCTN  Scanner/printer 33 inhibited from initiating a                                disconnect by the DAA.                                                STRBN   Start command not given to scanner/printer 33.                        ______________________________________                                    

As indicated by the legends appearing in FIG. 13, direct counterparts tomost of the above-identified signals are fed from the buffered outputsof the input/output devices 112 and 113 to control inputs of thetransceiver 38 by means of a suitable input interface 131, which isincluded to transform logic levels and to perform simple logicalfunctions. A notable exception exists in the case of ADSP2N, ADSP3N,ADSP4N and ADSP6N, which are generated by a decoder 132 in response tothe logic levels of automatic dialer speed select signals ASPSAN, ASPSBNand ASPSPN provided under program control. ASPSAN and ASPSBN allow forfour different bit combinations (00, 01, 10 and 11) and, therefore, aresufficient to indicate whether the scanner/printer 33 is to operate at adocument transmission rate of two, three, four or six minutes/page.ASPSPN is included to provide the additional bit that is necessary tosignal whether the document transmission rate of the scanner/printer 33is to be remotely determined or not.

The output signals of the Xerox 200 Telecopier transceiver, which aresampled under program control by the automatic dialer 31, are:

    ______________________________________                                               Significance of True or High ("1")                                     Signal Logic Level State                                                      ______________________________________                                        SCANS  The trial edge switch (not shown) in the ADF 41                               is actuated.                                                           TRAYS  At least one document remains in the input tray 43                            of the ADF.                                                            ENBM   The billing meter (not shown) within the scanner/                             printer 33 is enabled.                                                 XVID   The transmitted video represents a black picture                              element (white picture elements are represented                               by a low ("0") logic level signal).                                    ELCLK  A clock signal generated internally of the                                    scanner/printer 33.                                                    LSYNC  A scan line-by-scan line synchronizing signal                                 generated internally of the scanner/printer 33.                        TESTM  Scanner/printer 33 in a test mode.                                     AUTOP  Scanner/printer 33 in a print mode.                                    GSTRB  A gated start button indication from the                                      scanner/printer 33.                                                    DA-TC  Data available from the scanner/printer 33.                            ______________________________________                                    

Fig. 14 shows that direct counterparts of each of these signals are fedthrough an appropriate output interface 133 to respective ones of thegated inputs of the input/output device 112.

To enable the automatic dialer 31 to initiate a start by the transceiver38 under program control, one of the buffered outputs of theinput/output device 112 is used to apply a start signal ASTBP (automaticdialer start button push) to the transceiver 38. The start signal ASTBPis set to a high ("1") logic level under program control only when theautomatic dialer 31 is executing a manual or delayed start instruction.

Turning to FIG. 12, the CBS 1001F data access arrangement 39 employed inthe illustrated embodiment completes a voice/data path DR-DAA to acommunications link when supplied with control signals indicating thatdata is available DA-DAA and that an off-hook instruction OH-DAA hasbeen given. A ring detect signal RI-DAA and a switch hook signal SH-DAAare generated internally of the DAA 39 when a ringing voltage is appliedand when the voice/data path DR-DAA is complete, respectively.

In keeping with this invention, provision is made for generating theDA-DAA and OH-DAA input control signals for the DAA 39 under programcontrol. Furthermore, the status of the DAA 39 is monitored underprogram control. In this instance, there is an interface 134 between theDAA 39 and the automatic dialer 31 which performs several importantlogical functions in addition to the necessary logic leveltransformations.

As shown, the input signals applied to the DAA interface 134 are:

1. The ring detect RI-DAA and switch hook detect SH-DAA signals suppliedby the DAA 39;

2. automatic dialer switch hook (ASH) and an off-hook inhibit (OHINH)signals which are supplied by the input/output device 113 under programcontrol -- the ASH signal indicates that the handset 35 of the automaticdialer 31 is off hook and OHINH signal is an instruction to inhibit theDAA 39 from going off hook under the control of the automatic dialer 31;

3. Automatic dialer off-hook (AOH), ready (ADA) and ring enable (RIENBL)signals which are received from a discrete output buffer register 135(FIG. 11) which, in turn, is loaded by the accumulator 116 under programcontrol -- the AOH, ADA and RIENBL signals indicate whether theautomatic dialer 31 is on-line, ready and prepared for an incoming call,respectively; and

4. A 777 Hz signal gated at a 24 Hz rate which is provided by an ANDgate 136 (FIG. 14) in response to 777 Hz and 24 Hz input signalssupplied by a multistage frequency divider 137 which, in turn, issupplied with a TTL compatible input signal at the A clock rate of 199Hz by the input/output device 112.

The functions the DAA interface 134 performs in response to these inputsignals include:

1. Supplying the DAA 39 with a DA-DAA control signal whenever theautomatic dialer is in a ready state as indicated by the ADA signal andwith an OH-DAA control signal whenever the automatic dialer is on lineas indicated by the AOH unless the automatic dialer is requesting thatthe DAA 39 be inhibited from going off hook as indicated by the OHINHsignal;

2. Feeding to the gated inputs of the input/output device 113, theDA-DAA and OH-DAA control signals being fed to the DAA 39, a ringfeedback signal RIFB when a ring detect signal RI-DAA is present, asignal RI-TC indicating that there is an incoming call for thetransceiver 38 to answer when a ring detect signal RI-DAA and a ringenable signal RIENBL are present, a signal SH-TC indicating that thetransceiver 38 is off hook or busy when a switch hook signal is beingreceived from either the DAA 39 (SH-DAA) or the automatic dialer 31(ASH), and a gated ring feedback signal RISKFB when a ring detect signalRI-DAA, a ring enable signal RIENBL and the gated 777 Hz signal arepresent; and

3. Applying to a discrete input buffer 137 (FIG. 11) a switch hookfeedback signal SHFB in the absence of a DAA switch hook signal SH-DAA.

Here the gated ring feedback signal RISKFB is also used to drive anaudible alarm 138, whereby the operator is advised that the transceiver38 is about to answer an incoming call.

To bring this discussion into sharper focus, reference is additionallymade to FIGS. 17 and 18 for a review of the operation of the automaticdialer 31. When power is first applied, the program address register 108(FIG. 11) is reset or cleared, thereby automatically returning to thestarting address for a routine which initializes the automatic dialer 31and the transceiver 38 as indicated at 201. Next an idle loop routine isperformed until a condition requiring an entry into one of three branchroutines is detected. Sequential sampling is carried out while the idleloop routine is being performed to determine whether there is a ringingvoltage applied to the DAA 39 (FIG. 12) as indicated at 202, whether thedialer handset 35 (FIG. 1) is off hook, as indicated at 203, and whetheran autostart command has been given as indicated at 204. The branchroutines performed when one or the other of these conditions is detectedare dedicated to allowing the transceiver 38 to accept incoming calls,the manual mode of operation of the automatic dialer 31, and theautomatic mode of operation of the automatic dialer 31, respectively.

More particularly, if the automatic dialer 31 detects a high ("1") logiclevel ring feedback RIFB signal at the input/output device 113 (FIG. 12)while performing the idle loop routine, the program address register 108causes the ROM 106 to alternately enter into and exit from an incomingcall branch routine until a high ("1") logic level off-hook feedbacksignal OHFB is detected at the discrete input buffer 137 (FIG. 11) toconfirm that the transceiver 38 has answered the incoming call asindicated at 205. In this instance, as shown in FIGS. 13 and 14, theoff-hook feedback signal OHFB is fed into the input buffer 137 by thetransceiver output interface 133 in response to an off-hook signal whichis generated internally of the transceiver 38 when it is on line. Afterconfirming that the transceiver 38 is on line, the ROM 106 continueswith the branch routine to allow the automatic dialer 31 to determinewhether an address card is being scanned or not as indicated at 206 and,if not, whether the disconnect has been performed or not as indicated at207.

To detect the scanning of an address card, the BSVID video signalapplied to the input/output device 112 (FIG. 13) is more or lesscontinuously compared against a picture element sequence stored in theRAM 107 to represent the predetermined sequence of picture elementswhich are generated when the distinctive bar code 84 is being scanned.If an affirmative comparison occurs, the signals necessary to disconnectthe call are applied to the transceiver 38 and the DAA 39 under programcontrol as indicated at 208. Otherwise, the call is allowed to continueto normal completion as indicated at 207. In any event, when the call isdisconnected, the automatic dialer 31 returns under program control tothe idle loop routine.

If a high ("1") logic level hook switch HOOKSW signal is detected atanother discrete input buffer 138 while the idle loop routine is beingperformed, the automatic dialer 31 exits under program control from theidle loop routine and enters a branch routine dedicated to the manualmode of operation of the automatic dialer 31. As will be seen uponreferring to FIG. 9, the hook switch HOOKSW signal is taken from the setor Q output of a flip-flop 141 which is set and reset in response to theoff-hook and on-hook status, respectively, of the dialer hook switch 34.

Upon entering the manual operating mode branch routine, instructions aregiven under program control to read and store the digits the operatorenters via the keyboard 36 and then dial out, as indicated at 208. Thus,a review of how these functions are performed is in order.

As shown in FIGS. 11 and 15, the keyboard/display interface 115 for thisembodiment is the general-purpose keyboard/display device provided(under Part No. 10788) by Rockwell International Microelectronic DeviceDivision for use with the PPS-4 microcomputer. Thus, the keys of thekeyboard 36 are assembled in rows and columns to be readcolumn-by-column and row-by-row via bits 5-8 of the instruction/data bus104 when a keyboard-read instruction is given. In more detail, when suchan instruction is given, the column leads X₀ -X₄ are sequentiallystrobed during successive timing cycles while the row leads Y₀ -Y₃ areread into the accumulator 16 on bits 5-8 of the instruction/data bus 104for subsequent transfer to the exchange register 124. If a key withinthe column being strobed has been depressed, that bit will be at a high("1") logic level, rather than a low ("0") logic level, it beingunderstood that the leads Y₀ -Y₃ are normally held at a low ("0") logiclevel by virtue of being returned to a suitable low logic level supplysource (5VDC) through respective voltage dropping resistors 141-144. Thecontents of the exchange register 124 are, in turn, used to cause theprogram address register 109 to generate an address for reading apredetermined four bit representation of the depressed key into theaccumulator 116 for subsequent transfer back to an active data storageaddress within the RAM 108. The process is repeated as further keys aredepressed.

The binary representations (0-9) for the digit keys which are operatedare read in order into successive addresses of a segment of the activedata storage section of the RAM 108 which is dedicated to characterizingthe numerical indicia which are to be displayed. Another segment of theactive data storage section of the RAM 108 is dedicated to identifyingthe legends which are to be displayed.

To display the appropriate digital indicia and/or legends on the display92, there are separate addresses within the display dedicated activedata storage section of the RAM 108 for each of the numerical and legenddisplay elements of the display 92. Those addresses are blanked, unlessdata is entered to indicate that the associated display element is to beilluminated. Numerical indicia to be displayed are each characterized byfour bits, thereby uniquely identifying the specific numeral (0-9). Alegend, on the other hand, is adequately characterized by setting apredetermined one of the four bit representation to a high ("1") or low("0") logic level, depending on whether the legend is to be displayed ornot.

If, say, the displayed digits and legends are to be updated, the fourbit representations for the numerical and legend display elements aretransferred, under program control, from the RAM 108 to be accumulator116 and then via bits 1-4 of the instruction/data bus 104 to thekeyboard/display interface 115 where the digit representations and thelegend representations are shifted into separate storage registers (notshown). The anodes LA₀ -LA₇ and DA₀ -DA₇ of the legend and numericaldisplay elements within the display 92 are sequentially strobed byappropriate drivers 145 and 146, respectively, while successive groupsof four bits each are being shifted out of both interface storageregisters. Furthermore, a steering bit DBS is applied to a pair ofswitches 147 and 148 to cause the drivers 145 and 146 to selectivelystrobe the anodes of the display elements on the lefthand side or theright-hand side of the display 92, depending on whether bits are beingshifted out of the upper halves or the lower halves of the interfacestorage registers. A decoder 149 sequentially decodes the four bitrepresentations DA1-DA4 of any numerical indicia which are to bedisplayed, thereby energizing appropriate ones of the cathode segmentsof the numerical display elements in timed synchronism with the strobingof the anodes of the different elements by which successive ones ofthose indicia are to be displayed. As previously mentioned, one bit DB1is sufficient to indicate whether a legend is to be displayed or not.Thus, a switch 151 is operated in response to that one bit DB1 of eachof the four bit legend representations to selectively energize thecathodes of the legend display elements in timed synchronism with thestrobing of the anode of any legend display element which is to beilluminated. Of course, legends and numerics may be displayed jointly orindependently under program control.

Dialing is accomplished by pulsing the autodialer off-hook signal AOH(FIGS. 11 and 15) or by generating suitable dual tone, multiplefrequency (DTMF) dialing signals through the use of a tone generator 153(FIG. 10). A switch 102a (FIG. 11) is set by the operator to input ahigh ("1") or low ("0") logic level signal to the discrete input buffer138, thereby indicating whether DTMF or pulse-type dialing is to beemployed. In either event, the digits to be dialed are represented bythe four bit numerical representations stored in the active data,display dedicated segment of the RAM 108 when there is a call to beplaced so that those digits are more or less concurrently displayed anddialed.

If pulse-type dialing is selected, the four bit representations of thedigits to be dialed are sequentially transferred, under program control,from the active data section of the RAM 108 to a dial counter addresswithin the RAM 108. In the course of that process, any "0" digit isconverted to a four bit representation of "10". Each digit is dialed outbefore the next digit is read into the dial counter. To that end, theautomatic dialer available ADA signal is held at a low ("0") logic levelwhile the automatic dialer off-hook AOH signal provided by the discreteoutput buffer 135 (FIG. 11) is alternately switched between a high ("1")and a low ("0") logic level, under program control, at a frequency andwith a repetition rate selected to cause the DAA off-hook OH-DAA controlsignal (FIG. 12) to emulate a dialing pulse. As each dialing pulse isgenerated, the value of the digit being dialed is decremented by one,until the value reaches zero to confirm that the dialing of the digithas been completed. After a suitable delay, the process is repeated. Assuccessive digits are transferred into the dial counter section of theRAM 108, a count stored within a dial location address of the RAM 108 isincremented by one, under program control, so that the last possibledigit to be dialed out is marked by the dial location counter reaching apredetermined value, thereby allowing for a timely termination of thedial out routine.

For DTMF dialing, the four bit representations of the digits to bedialed are sequentially transferred to the TTROW1-TTROW4 andTTCOL1-TTCOL4 inputs of the tone generator 153 (FIG. 10) under programcontrol. Two input/output instructions are utilized per digit, wherebythe four bit representation of each digit is fed through theinput/output device 114 to the TTROW1-TTROW1 inputs of the tonegenerator 153 in response to one instruction and to the TTCOL1-TTCOL4inputs in response to another instruction. The tone generated by thetone generator 153 is fed through a normally open contact 154 of a relay155 (FIG. 9) to the voice/data path DR-DAA provided by the DAA 39 (FIG.12) which, in turn, applies it to the communications link. Again, thedial location counter provided by the RAM 108 is used to signal thecompletion of the dial out routine, and a suitable interval of time ismaintained between the dialing of successive digits to avoid confusion.The tone generator 153 is, however, isolated from the transceiver 38 toavoid applying false data or control signals to the transceiver 38. Tothat end, the data path DR-TC for the transceiver 38 is coupled to thedata path DR-DAA of the DAA 39 through a normally closed contact 156 ofthe relay 155.

Returning now to FIG. 17 to complete the description of the manual modebranch routine, it will be seen that the ROM 106 recycles to the dialout instruction 208 until the dialer hook switch HOOKSW signal at theinput buffer 138 drops to a low ("0") logic level, thereby indicatingthat the dialer handset 35 is in place on its hook switch 34 asindicated at 209. A high ("0") logic level ARELAYN is then fed from theinput/output device 113 (FIG. 12) to the coil 157 of the relay 155 (FIG.10) to ensure that the data path DR-TC of the transceiver 38 is cutthrough to the voice/data path DR-DAA of the DAA 39, and a predeterminedtime out period starts to run. Specifically, a high ("1") logic leveloff-hook feedback OHFB signal must be detected at the discrete inputbuffer 137 before a high ("1") logic level TIMEOUT signal is detected atthe other discrete input buffer 138 (FIG. 11). Otherwise, the ROM 106will return to idle loop routine due to a failure of the transceiver 38to start, as indicated at 211. If the transceiver 38 does start, thecommunication continues to a normal disconnect, as indicated at 207,unless a forced disconnect 208 is called for as a result of thetransceiver 38 starting to scan an address card, as indicated at 206. Ofcourse, when a normal or forced disconnect occurs, the ROM 106 returnsto the idle loop routine.

As shown in FIGS. 10 and 11, programmed delay timing is performed by aprogrammable counter 161 which sets a flip-flop or latch 162 when a timeout occurs, thereby causing the TIMEOUT signal provided by the latch 162to go to a high ("1") logic level. When delay timing is called for, thecounter 161 and the latch 162 are reset or cleared, under programcontrol, in response to a reset signal TIMEOUT supplied by theinput/output device 113 (FIG. 12). Further input/output instructions arethen given to cause a single or multiple place binary count to be loadedinto the counter 161 via outputs TBCD1-TBCD4 from the input/outputdevice 114. That count is then decremented toward zero in response toclock pulses supplied by frequency divider 137, whereby a time out issignalled when the count reaches zero. Here, the basic frequency to thedecrementing clock pulses is approximately 3.1 KHz. However, there is adivide-by-eight stage (not shown) in the clock input of the counter 161which is selectively bypassed if a control bit 8-BYPS supplied by theinput/output device 113 is set, under program control, to a high ("1")logic level. Therefore, if the counter 161 has, say, the capacity tostore a 16 place binary count, any time out period from 320 microsecondsto 2¹⁶ × 320 microseconds × 8 (to account for the divide-by-eightstage)-viz., 45 minutes--may be programmed into the counter 161.

Turning again to FIGS. 17 and 18, if an automatic start command isreceived, as indicated at 204, while the idle loop routine is beingperformed, the ROM 106 branches into an automatic dialing routine. A"START" button on the keyboard 36 may be depressed to generate anautomatic start command or the actual or running time-of-day kept by anAM-PM clock 163 (FIG. 10) may come into coincidence with a delayed starttime-of-day previously read into the RAM 108 through the use of thekeyboard 36. For that reason, the keyboard 36 and the AM-PM clock 163are periodically read while the idle loop routine is being performed,and the running time-of-day indication provided by the clock 163 isperiodically compared against any delayed start time-of-day-stored inthe RAM 108. Any "START" button command and any delayed start time ofday are read into the RAM 108 by the previously described keyboardreading process. Therefore, there is no reason to repeat thatdescription. Instead, it suffices to note that the entry of atime-of-day for a delay start is initiated by depressing the "TIME SET"key on the keyboard 36. Thereafter, an appropriate one of the "AM" or"PM" keys is depressed, and then the digit keys are operated to identifythe AM or PM hour and minute for the delayed start, starting with thedigit for the most significant unit of time and proceeding in turn tothe digit for the least significant unit of time. The four bitrepresentation for the "AM" or "PM" key and the time identifying digitkeys are stored in predetermined addresses within the active datastorage section of the RAM 108 for display on the right-hand side of thedisplay 96 and for comparison against the actual time-of-day kept by theAM-PM clock 163. Those bits are, however, transferred into a temporarystorage section of the RAM 108 whenever the ROM 106 branches into themanual mode routine, a test routine (not shown) or a recall routine, orif an automatic start command is given.

As shown in FIG. 10, the AM-PM clock 163 for this embodiment is atwelve-hour clock which is driven by the ordinary 60 Hz line frequency.A normally open switch 102b is included so that the operator may set theclock 163 to the correct time by selectively applying a reference levelvoltage (say, ground) to a FASSET input for coarse adjustments or to aSLOSET input for fine adjustments. Suitably, the AM or PM significanceof the running time-of-day is indicated by alternately setting andresetting the flip-flop 126 (FIG. 1) as the running time of-day rollsover from the last minute of the twelfth hour to the first minute of thefirst hour.

A self-contained strobe within the clock 163 provides a four bit strobepattern on strobe leads HR10, HR1, MIN10 and MIN1 to identify theparticular unit or place position of the running time-of-day which iscurrently represented by the four bit binary representation on digitleads CBCD1-CBCD8. Thus, to read the clock 163, appropriate input/outputdevice 114, whereby the strobe leads HR10, HR1, MIN10 and MIN1 are readto obtain a four bit representation of the current value for thatparticular place position. The process is repeated, placeposition-by-place position, to obtain a full characterization of theexisting time-of-day. The four bit representations of the existingvalues for those place positions are read into the active storagesection of the RAM 108 for display on the left-hand side of the display96, but are subject to being displaced therefrom if the ROM 106 branchesinto the manual mode routine, a test routine or a recall routine, or ifan automatic start command is given.

If a delayed start time is loaded into the RAM 108, the actualtime-of-day and the time-of-day selected for the delayed start areperiodically compared under program control, to detect coincidence. Tothat end, the AM-PM indications, the more significant place values, andthen the less significant place values for the actual and delayed starttimes are compared in order, until a lack of coincidence is found.

Returning to FIGS. 17 and 18, if the actual time-of-day coincides withthe time-of-day selected for a delayed start, or if an immediate startcommand is entered by operating the "START" key, the ROM 106 branchesinto an automatic start routine under program control to determinewhether the start command is to be executed or not as indicated at 212.If a dedicated recall memory section of the RAM 108 is full as indicatedby, say, the flip-flop 127 being in a set state, if the transceiver 38is off-hook as indicated by a high ("1") logic level off-hook OHFBsignal at the input buffer 137, or if the input tray 42 of the automaticdocument feeder 41 (FIG. 2) is empty as indicated by a low ("0") logiclevel BTRAY signal at the input/output device 113, the ROM 106 exitsfrom the automatic start routine and returns to the idle loop routine.Otherwise, the ROM 106 provides on instruction 213 which causes thetransceiver 38 to feed and start to scan the first or bottommostdocument in the input tray 42 of the ADF 41 (FIG. 2). The BYSYNC signalapplied to the input/output device 113 is monitored for apositive-to-negative transition which marks the completion of the firstscanning cycle, and then the count representing a predetermined time outperiod is loaded under program control into the programmable counter 161as previously described.

If the counter 161 times out before the distinctive bar code 84 (FIG. 5)along the borders of an address card is detected, the ROM 106 provides,as indicated 214, an instruction 215 which causes the document feeder 41to eject the document and directs that appropriate entries to be made inrecall memory, as indicated at 216. The absence of the bar code 84indicates that the document was not an address card or a pause card. Ifthere is another document in the input tray 42 as indicated by a high("1") logic level BTRAY signal at the input/output device 113, the ROM106 returns to the feed and scan instruction 213. If not, the ROM 106returns to the idle loop routine, as indicated at 217.

If the bar code 84 is detected, another predetermined count is loadedinto the counter 161 under program control to provide a fixed time-outperiod for detecting the bar code 87 marking the first row of theaddress card instruction field 85. Should a time out occur, the ROM 106provides the eject instruction 215 and the recall entry instruction 216and then looks for another document in the ADF tray 42, as indicated at217, on the assumption that the address card is misoriented.

When a border bar code 84 and a row bar code 87 are detected on time,the ROM 106 provides instructions 217 to (1) read the mark senseidentified terminal and dialing control instruction in the instructionfield 85 of the address card into the active data section of the RAM 108for display on the display 96; provide the transceiver 38 with theappropriate input control signals for executing the terminal controlinstructions; load a preselected count into a predetermined radialcounter address within the RAM 108; and cause the document feeder 41 toeject the address card after the last instruction has been read.

As previously mentioned, the mark sense identified terminal and dialingcontrol instructions are decoded by utilizing the bar code 87 precedingeach row of the instruction field 85 as a timing reference. That processyields a four bit representation for each mark sense identifiedinstruction that is scanned, unless two or more mark sense identifiedinstructions are encountered during the scanning of any given row. Ifthat occurs, blanks are loaded into the RAM address for the instructionfrom that row under program control. To that end, the flip-flop 126(FIG. 11) is reset in response to the detection of each bar code 87 andset in response to the detection of each mark sense identifiedinstruction, and blanks are loaded into the RAM address for any givenrow if a mark sense identified instruction is detected while theflip-flop 126 is in a set state.

Each time a row bar code 87 is detected while the flip-flop 126 is in aset state, a predetermined count is loaded into the counter 121 toobtain a high ("1") logic level TIMOUT signal at the discrete inputbuffer 137 whenever two rows or an equivalent segment of the addresscard is scanned without detecting a mark sense identified instruction.That, in turn, causes the ROM 106 to issue an instruction for ejectingthe address card from the ADF 41 and to initiate a dial-out routine asindicated at 219.

The decoded dialing and terminal control instructions are stored in theactive data section of the RAM 108 for display on the display 96. Pulseor DTMF dialing is performed in response to these instructions in themanner described above, except that initial and intermediate dial tonesare accommodated by pausing for a predetermined period of time, if blinddialing has been selected, or by waiting until dial tone is detected, ifdial tone response dialing has been selected. A switch 102c is manuallypositioned by the operator to apply a high ("1") or a low ("0") logiclevel signal to an input of the discrete input buffer 138 (FIG. 11),thereby reflecting the option which has been selected.

For blind dialing, a predetermined count is loaded into the programmablecounter 161 (FIG. 10) whenever the four bit representation of an initialor intermediate dial tone is read out of the RAM 108 during the dial-outroutine. That routine is then suspended for a predetermind amount oftime, until a high ("1") logic level TIMOUT signal is received at theinput buffer 137 (FIG. 11) to indicate that the time allotted to theacquisition of dial tone has expired.

When dial tone responsive dialing is selected, a predetermined time outperiod is allotted to the acquisition of any initial or intermediatedial tone, but the dial-out routine does not resume until there is ahigh ("1") logic level busy back/dial tone signal BUSYDT at theinput/output device 114 (FIG. 10) to confirm that dial tone has beenreceived. If a time out occurs before dial tone is received, the ROM 106suitably advances under program control to the redial subroutinedescribed hereinbelow.

As shown in FIG. 9, to perform the busy back/dial tone detectionfunction, this embodiment includes a bandpass filter 171, which has apassband roughly equal to the passband of an ordinary voice gradetelephone channel, for coupling the data/voice path DR-DAA of the DAA 39(FIG. 12) to a series detector circuit comprising a 1500 Hz notch filter172, a limiter 173, a 300 Hz - 700 Hz bandpass filter 174 and athreshold detector 175. Much of the extraneous noise outside the 300 Hzto 700 Hz range normally used for dial tone and busy back signalling iseliminated by the bandpass filters 171 and 174, but the notch filter 172provides an additional measure of protection against a false BUSYDTindication by sharply attenuating any energy at the 1500 Hz frequencyused for handshaking purposes. Even with that protection, there may becircumstances where sufficient energy applied to the threshold detector175 to cause it to generate a high ("1") logic level BUSYDT signal inthe absence of a busy back or dial tone signal, but that situation isstraight forwardly dealt with by validating the BUSYDT signal only if itremains at that logic level for a suitably long period of time. Ofcourse, the limiter 173 protects the bandpass filter 175 and thethreshold detector 176 against the potentially damaging effects ofexcesively high signal levels.

When dialing is completed, the ROM 106 provides instructions 221 whichcause the tone generator 153 (FIG. 10) to feed an appropriatehandshaking signal through the DAA 39 in an attempt to establishcommunications with the remote terminal being called. Specifically, forthe Xerox 200 Telecopier transceiver compatible case, the tone generator153 is instructed to supply a combination of 1200 Hz tones or analternating 1800/1500 Hz tone, depending on whether the transceiver 38is to operate in a transmit mode or a receive mode as determined by theterminal control instructions stored in the RAM 108. During the dialingan initial hand-shaking, a low ("0") logic level ARELAYN signal isgenerated under program control so that the tone generator 153 is cutthrough to the voice/data path DR-DAA of the DAA 39. At the same time,high ("1") logic level AMIC and AEAR signals are provided to opencircuit switches 176 and 177 which are connected in series with thetransmitter 35a and receiver 35b sections of the handset 35.

Another count is loaded into the counter 161 when dialing is completedto provide the remote terminal with a predetermined amount of time torespond to the handshaking signal supplied by the tone generator 153.During this period, the input/output device 114 (FIG. 10) is sampled fora high ("1") logic level busy back/tone detect signal BUSYDT, asindicated at 222, and for a high ("1") logic level acknowledgment signalVGRACK, as indicated at 223. Additionally, the input buffer 137 (FIG.11) is sampled for a high ("1") logic level time out signal TIMOUT. Ifan acknowledgment is detected, the ROM 106 provides the necessaryinstructions for cutting the transceiver 38 through to the voice/datapath DR-DAA of the DAA 39 and for otherwise preparing it for operation,as indicated at 224-230. If, on the other hand, a busy link condition isdetected, the ROM 106 initiates a redial subroutine, as indicated at241-243. Or, if a time out occurs without detecting a busy back signalor an acknowledgment signal, the ROM 106 aborts the job with anappropriate recall entry instruction 216.

In keeping with the customary handshaking protocol of a Xerox 200Telecopier transceiver, the remote terminal is expected to generate anintermittent 1500 Hz acknowledgment or ready signal in response toeither of the handshaking signals which can be provided by the tonegenerator 153. Thus, to provide for the detection of such anacknowledgment signal, the voice/data path DR-DAA of the DAA 39 iscoupled through the bandpass filter 171 to another series detectorcircuit which, as shown in FIG. 9, comprises a 300 Hz - 700 Hz notchfilter 181, a protective limiter 182, a 1500 Hz bandpass filter 183, anintegrator 184 and a threshold detector 185. Accordingly, a high ("1")logic level acnowledgement signal VGRACK is supplied by the thresholddetector 185 only if there is a substantial amount of persistent energyat or about the 1500 Hz center frequency of the bandpass filter 183.Transients are in large part ignored because of the time constantassociated with the integrator 184. Additionally, the threshold detector185 advantageously includes a voice guard circuit (not shown) to prevent1500 Hz energy accompanied by significant amounts of energy at othervoice band frequencies from being misinterpreted as an acknowledgmentsignal. Nevertheless, the preferred practice is to require that theVGRACK signal remain at the high ("1") logic level for a predeterminedperiod of time before being accepted as a valid indication that anacknowledgment has been received.

If a valid high ("1") logic level acknowledgment detect signal VGRACK isreceived before the post-dialing time out period expires, adetermination is made, as indicated at 224, whether the terminal controlinstructions which were given call for the transceiver 38 to operate ina transmit mode or a receive mode. If the transceiver 38 is beingoperated in the receive mode, the off-hook OHFB signal at the inputbuffer 137 is repeatedly sampled, under program control, to detect thedisconnect 225 which occurs when the communication is completed. At thatpoint, the ROM 106 is returned to the starting point for the automaticmode branch routine to determine, as indicated at 212, whether anotherautomatic start may be carried out.

In the event that the inquiry 224 leads to the conclusion that thetransceiver 38 is being instructed to operate in a transmit mode, theROM 106 responds by providing an instruction 226 to feed and scan thenext document. As the lead edge of that document is being scanned, theBSVID signal appearing at the input/output device 112 (FIG. 14) issampled to determine, as indicated at 227, whether an address card or apause card is being scanned. If so, the ROM 106 provides a forceddisconnect instruction 228 to disconnect the call and to terminate thefeed and scan.

Returning for a moment to FIG. 5B, it will be seen that a pause card 88has a distinctive border bar code 89 along the leading and trailingedges of its front and rear sides. The characterizing feature of thepause card bar code 89 is that it contains the address card border barcode 84 in additon to a distinguishing code segment 90. Moreover, unlikethe address cards 81a-81c (FIG. 5A), the pause card 89 is symmetricaland, therefore, does not impose a critical orientation requirement.

Turning back to FIGS. 17 and 18, when the transceiver 38 is operating inits transmit mode, the ROM 106 repeats the feed and scan next documentinstruction 226 as necessary to allow for the transmission of theinformation content of successive subject copies destined to the sameremote terminal. Each of those documents is examined to determinewhether a forced disconnect instruction 228 should be given because anaddress card or a pause card is being scanned. Furthermore, the off-hookfeedback OHFB signal is sampled to determine, as indicated at 229,whether a normal disconnect has occurred.

When a forced disconnect instruction 228 is given, a determination ismade, as indicated at 231, whether the scanning of the distinctiveborder bar code 90 (FIG. 5) of a pause card was responsible for thatinstruction being given. If so, a predetermined count is loaded into theprogrammable counter 161, under program control, to suspend theautomatic mode of operation of the automatic dialer 31 for apredetermined period of time as indicated at 232. If not, or if a normal(non-program initiated) disconnect was detected, the ROM 106 immediatelyreturns to the starting point of the automatic mode branch routine todetermine, as indicated at 212, whether another automatic start ispermissible.

As will be recalled, the programmable counter 161 (FIG. 10) for theparticular time-out embodiment has the capacity to provide a time-outperiod of up to 45 minutes. Suitably, the delay 231 allotted to eachpause card is selected to equal a predetermined fractional portion ofthat period, such as one half or, in other words, 22.5 minutes. Thatprovides ample time for the transceiver 38 to accommodate a few incomingcalls or for an operator to use the automatic dialer 31 in its manualmode to place a few outgoing calls. Moreover, if additional time isneeded, two pause cards may be stacked one after another in the inputtray 42 to take advantage of the full capacity of the counter 161. Itshould be noted that when an automatic start command is given, the ROM106 provides appropriate instructions (not shown) for initializing thetransceiver 38 in its test mode to scan at its two-minute documenttransmission rate, and that the receiver 38 remains in that mode untilcontrary instructions are provided as a result of scanning an addresscard with mark sense indicia identifying terminal control instructionsor as a result of starting to scan a document which does not have thedistinctive address card border bar code 84.

When the pause card initiated delay period expires, as indicated by theappearance of a high ("1") logic level TIMOUT signal at the input buffer137 (FIG. 11), the BTRAY signal applied to the input/output device 112is sampled to determine, as indicated at 217, whether the ADF tray 42(FIG. 2) is now empty or not. If so, the ROM 106 returns to the startingpoint 212 for the idle loop routine. If not, the ROM 106 providesanother feed and scan instruction 213 to re-initiate the automatic modeof operation of the dialer 31.

In passing, it is worth mentioning that each pause card 90 should bepreceded by and followed by another pause card or by an address card, asshown in FIG. 4. A flag 233 is set after an initial correctly marked andoriented address card is scanned to allow the transceiver 38 to scanpause cards, despite the negative result of the address card correctinquiry 214, as indicated at 234. That inquiry 214 does, however, leadto a job abort with an appropriate recall entry 216, if a pause card isnot preceded by and followed by another pause card or an address card.

Focusing now on the redial subroutine, it will be seen that if a high("1") logic level busy back/dial tone detect signal BUSYDT is applied tothe input/output device 114 (FIG. 10) during the post-dial out time outperiod, an inquiry 241 is made, under program control, to determinewhether the redial count stored in the RAM 108 is equal to zero. If thatcount has not yet reached zero, the ROM 106 issues a delay instruction242 and an instruction 243 to decrement the redial counter by one beforereturning to the dial-out instruction 219 for the purpose of makinganother attempt at placing the call in accordance with the dialinginstructions in the active data section of the RAM 108. If a busy linkis repeatedly encountered, the redial count ultimately reaches zero.When that occurs, the ROM 106 exits from the redial subroutine with aninstruction 216 to make an appropriate entry into the recall memorysection of the ROM 108. That and the other recall memory instructionswhich have been referred to hereinabove are described in further detailin a commonly assignd and concurrently filed United States patentapplication of R. Heckman and J. Torpie for "Automatic Dialer Having aRecall Memory."

Desirably, there is a manually operable switch 102d for applying a high("1") or a low ("0") logic level control signal to the discrete inputbuffer 138 so that a long or short redial delay period may be selectedby the operator. That option is easily accommodated by simply alteringthe count that is loaded into the programmable counter 161 whenexecuting the delay instruction 242 to reflect the setting of the switch102d.

VI. CONCLUSION

In view of the foregoing, it will now be understood that an automatictelephone dialer which is particularly well suited for use withfacsimile terminals and the like has been provided.

What is claimed is:
 1. In an automatic telephone dialer for placingoutgoing telephone calls from a terminal having a raster input scannerfor sequentially scanning address cards bearing mark sense indiciaidentifing telephone numbers to which respective ones of said calls areto be placed; said address cards having a common, distinctiverecognition code; the improvement comprising means for interrupting thescanning of successive ones of said address cards for a predeterminedperiod of time in response to the scanning of a supplemented recognitioncode containing said distinctive code.
 2. The improvement of claim 1wherein said supplemented recognition code is carried by a pause card.3. The improvement of claim 2 wherein said terminal is a facsimileterminal having an automatic document feeder for serially feedingaddress cards, any pause cards and any subject copies past said inputscanner.
 4. The improvement of claim 3 wherein said address cards alsocarry mark sense indicia identifying control instructions for saidfacsimile terminal, and said automatic dialer includes means forcontrolling the operation of said facsimile terminal in accordance withsaid terminal control instructions.
 5. The improvement of claim 4wherein the delay period is proportional to the number of pause cardssequentially scanned, at least up to a predetermined limit.